Legion5

"performance plugs, wires, and coil for better spark. " I don't know if I beleive in doing anything more than adding colder plugs, has anyone shown dyno gains with "better" plug systems?

I'm also interested in how much HP headers give, I'd hope about 8-12 for the money.

I'm still looking for the ball park figure. I also forgot to mention I'm using 3.73's.

chrisc

If the ones they will be selling are exactly the same as the prototype, you should expect about 320rwhp on an auto and 340rwhp with an manual (DynoJet) with full bolt ons. Oh, and a good custom tune, as any other f/i system, is definitely required.

"Full bolt ons" include:
-H/O X kit
-water/meth kit (dont neglect this one, I am guessing it is worth ~15whp)
-TB
-full exhaust (headers to mufflers)
-ignition wires and coil pack
-alum driveshaft

If you are not a fan of water/meth cooling, and still want extra power, you could probably safely run 12-14psi with the aftercooler installed.

pat6674u

I'm pretty sure my car is putting down close to if not better stock GT HP/TQ. Non-intercooled, no meth, Cali-spec set-up. Adding just the hi-po should put you close to 300 rwhp. Intercooler will allow the boost to go up which should transfer into more HP. An article by Ken Belle on SC myths states 1 psi boost should equalan 7% increase in hp (Modified Mustangs, December 2007). I hope to expect a fairly significant increase in hp with the IC running 12 psi rather than the 6 psi I'm currently at. I'm pretty certain the 7% hp gain is at the crank rather than the wheels but doing the math from my car stock, that number is pretty close. Anyone care to comment on this because my knowledge is limited. Essentially the S/C is able to run a higher psi because the IC is able to handle the extreme heat caused by this process. Methanol is a similar process but cools the air down at the inlet pipe using a spray method. I know I've gone off on a bit of a tangent but the point is an intercooled X should be capable of smoking a stock GT and lightly modded GT's. The GT will have to have it's own power adder to beat the intercooled X. I encourage debate on this because like I said, my knowledge is limited to just book reading and not actual experience.

elroyjetson_1978

It's not really for immediate hp as much as being able to tune the timing and spark for better combustion resulting in more power

pat6674u the xcharger hi-po will walk a bone stock gt but a mildly modded gt will walk a xcharger hi-po. with the IC the x should, with tuning be back to walking bolt-on gts

LX200

I have the HiPo kit at 3.0 PSI... it seems this setup puts out about 265 RWHP, which equates to probably slightly over 300 at the crank. That would put the 3.0 HiPo kit in the general range of a GT... as others have said, so many other things would actually dictate the results in a drag race.

I think I heard the intercooer is worth like 35 degrees cooling? I think current estimates are for 35 more RWHP... this puts you at about 300 RWHP for the 3.0 HiPo kit, easilybetter than a stock GT. Now go to the 2.8 pulley, and you are probably looking at 335 RWHP or 365 at the crank... easily better than an CAI'ed GT.

The Potato

Should something be done to the rear axle? I heard it craps out past ~350rwhp.

chrisc

Yes, the rear should be built when entering the mid 300rwhp's. However, I really doubt that any S/C kit is going to bring a car there as easily as most people are hoping with the IC X. In reality, most IC H/O X's will probably be around the 300rwhp mark. Look at the Vortechs and Prochargers if you want to see what the IC H/O X numbers will look like.

Really, I would not worry about the rear end with any S/C system if you do not plan on putting drag radials on it. I am planning to run about 340rwhp, and the only thing I have done to the rear end is a FRPP tlok.

Trmachuno

Fixed^

And as other's have said, to max out your gains for the f/i Legion5, You can do:
-Throttle body-10rwhp tuned on f/i engine(guess)
-headers-10rwhp for shorties morefor lt'son f/i engine(guess)
-Wet-x kit-10-15rwhp
-aluminum driveshaft
-heads and cam tuned for x-charger(if you wanna go that far but it's mucho dinero and will show a nicegain)
There's other weight reduction androtational mass stuff you can do if you want more speed. Good Luck!

Legion5

I have an aftermarket rear axel with a limited slip, it's lighter than stock and good for 600hp.